A judge in the U.S. city of Cleveland has revoked the U.S. citizenship of an accused Nazi death camp guard. As a result, retired autoworkers John Demjanjuk could face deportation.

U.S. District Judge Paul Matia ruled that the government proved in a trial eight months ago that 81-year-old John Demjanjuk served as a willing guard at Nazi camps during World War II. He also ruled that Demjanjuk lied about his past when he first came to the United States in 1952. Demjanjuk could be detained and deported or extradited to another country for criminal prosecution.

Assistant U.S. Attorney Michael Chertoff said, in any case, Demjanjuk does lose his citizenship. "Individuals who participated in the Third Reich's persecution of innocent civilians are unworthy of the privilege of American citizenship," he said.

This is the second time Demjanjuk has been stripped of his American citizenship. The first time was in 1981 at his first war crimes trial. The U.S. government had accused him of being the brutal guard "Ivan the Terrible" at the Treblinka concentration camp in Poland. Demjanjuk was extradited to Israel, where he was convicted of war crimes and crimes against humanity, and sentenced to death.

But in 1993, courts in both the United States and Israel said there was serious doubt whether Demjanjuk actually was Ivan the Terrible. Israel reversed its conviction and returned Demjanjuk to the United States. In 1998 his citizenship was restored, but in 1999 the U.S. government filed new charges, saying that, even if Demjanjuk was not Ivan the Terrible, he was a Nazi death camp guard.

Demjanjuk has said all along that he served in the Soviet Army, was captured in 1942 and remained in German prisoner-of-war camps.

His lawyers say Demjanjuk may have been confused with a cousin with the same name who lived in the same Ukrainian village. Demjanjuk plans to appeal this latest court ruling.